I ran into the error "Could not find com.android.tools.build:gradle:3.6.2" when trying to launch my React Native app. Here's my project configuration and how I resolved it:

Project Configuration Files #

Root build.gradle #

buildscript {
    ext {
        buildToolsVersion = "30.0.0"
        minSdkVersion = 16
        compileSdkVersion = 28
        targetSdkVersion = 28
    }
    repositories {
        jcenter()
    }
    dependencies {
        classpath 'com.android.tools.build:gradle:3.6.2'
        classpath 'com.google.gms:google-services:4.2.0'
        // NOTE: Do not place your application dependencies here; they belong
        // in the individual module build.gradle files
    }
}
allprojects {
    repositories {
        mavenLocal()
        maven {
            // All of React Native (JS, Obj-C sources, Android binaries) is installed from npm
            url("$rootDir/../node_modules/react-native/android")
        }
        maven {
            // Android JSC is installed from npm
            url("$rootDir/../node_modules/jsc-android/dist")
        }
        google()
        jcenter()
    }
}

App Module build.gradle #

apply plugin: "com.android.application"
apply from: "../../node_modules/react-native-vector-icons/fonts.gradle"
import com.android.build.OutputFile

project.ext.react = [
    entryFile: "index.js",
    enableHermes: false,  // clean and rebuild if changing
]

apply from: "../../node_modules/react-native/react.gradle"

def enableSeparateBuildPerCPUArchitecture = false
def enableProguardInReleaseBuilds = false
def jscFlavor = 'org.webkit:android-jsc:+'
def enableHermes = project.ext.react.get("enableHermes", false);

android {
    compileSdkVersion rootProject.ext.compileSdkVersion

    compileOptions {
        sourceCompatibility JavaVersion.VERSION_1_8
        targetCompatibility JavaVersion.VERSION_1_8
    }

    defaultConfig {
        applicationId "com.shadowman.showcase"
        minSdkVersion rootProject.ext.minSdkVersion
        targetSdkVersion rootProject.ext.targetSdkVersion
        versionCode 200
        versionName "2.0.0"
    }
    splits {
        abi {
            reset()
            enable enableSeparateBuildPerCPUArchitecture
            universalApk false  // If true, also generate a universal APK
            include "armeabi-v7a", "x86", "arm64-v8a", "x86_64"
        }
    }
    signingConfigs {
        debug {
            storeFile file('debug.keystore')
            storePassword 'android'
            keyAlias 'androiddebugkey'
            keyPassword 'android'
        }
    }
    buildTypes {
        debug {
            signingConfig signingConfigs.debug
        }
        release {
            // Caution! In production, you need to generate your own keystore file.
            signingConfig signingConfigs.debug
            minifyEnabled enableProguardInReleaseBuilds
            proguardFiles getDefaultProguardFile("proguard-android.txt"), "proguard-rules.pro"
        }
    }
    // applicationVariants are e.g. debug, release
    applicationVariants.all { variant ->
        variant.outputs.each { output ->
            // For each separate APK per architecture, set a unique version code
            def versionCodes = ["armeabi-v7a": 1, "x86": 2, "arm64-v8a": 3, "x86_64": 4]
            def abi = output.getFilter(OutputFile.ABI)
            if (abi != null) {  // null for the universal-debug, universal-release variants
                output.versionCodeOverride = versionCodes.get(abi) * 1048576 + defaultConfig.versionCode
            }
        }
    }
}

dependencies {
    // Firebase dependencies
    implementation "com.google.android.gms:play-services-base:16.1.0"
    implementation "com.google.firebase:firebase-core:16.0.9"
    implementation "com.google.firebase:firebase-messaging:19.0.0"
    implementation 'me.leolin:ShortcutBadger:1.1.21@aar'
    implementation fileTree(dir: "libs", include: ["*.jar"])
    implementation "com.facebook.react:react-native:+"  // From node_modules
    implementation 'androidx.appcompat:appcompat:1.1.0-rc01'
    implementation 'androidx.swiperefreshlayout:swiperefreshlayout:1.1.0-alpha02'

    if (enableHermes) {
        def hermesPath = "../../node_modules/hermes-engine/android/";
        debugImplementation files(hermesPath + "hermes-debug.aar")
        releaseImplementation files(hermesPath + "hermes-release.aar")
    } else {
        implementation jscFlavor
    }
}

// Run this once to be able to run the application with BUCK
task copyDownloadableDepsToLibs(type: Copy) {
    from configurations.compile
    into 'libs'
}

apply from: file("../../node_modules/@react-native-community/cli-platform-android/native_modules.gradle");
applyNativeModulesAppBuildGradle(project)

apply plugin: 'com.google.gms.google-services'

gradle-wrapper.properties #

distributionBase=GRADLE_USER_HOME
distributionPath=wrapper/dists
distributionUrl=https\://services.gradle.org/distributions/gradle-6.1.1-bin.zip
zipStoreBase=GRADLE_USER_HOME
zipStorePath=wrapper/dists

How to Fix the Error #

Potential Fixes to Try First #

1. Add google() to buildscript repositories
   The Gradle plugin com.android.tools.build:gradle is hosted in Google's Maven repository. Update your root build.gradle to include google() in the buildscript.repositories block:

   buildscript {
       repositories {
           google() // Add this line first
           jcenter()
       }
       // ... rest of your buildscript code
   }
   

2. Clean and rebuild the project
   Run these commands in your project root to clear cached files and rebuild:

   cd android
   ./gradlew clean
   cd ..
   npx react-native run-android
   

My Resolved Solution #

After testing the above steps without success, I identified the issue as network-related. Since I live in Crimea, enabling a VPN allowed Gradle to access the required Maven repositories and download the missing artifact, which fixed the error immediately.

Content sourced from Stack Exchange, question author: Shadowman